Lighting devices using arrays of light sources are of great interest for applications such as backlight for displays and illumination panels. Such arrays are typically made by arranging the light sources, such as for example LEDs (Light Emitting Diodes) on a large area PCB (Printed Circuit Board). Further, since illumination applications are desirable, often high power light sources are requested, causing a need for a heat sink on which the PCB is mounted. However, the large area PCB is relatively expensive. A lighting device of basically the presented kind is shown in WO 2007/124277, where the lighting device includes columns of LED light sources mounted on printed circuit boards. The boards are arranged on a heat sink. This prior art solution uses several smaller PCBs, which may reduce the cost to a certain extent. On the other hand, the wiring is increased, which is negative.